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El pòlip de Trembley: L'"animal-planta" que va sacsejar la biologia del segle XVIII

2013

Els experiments d’Abraham Trembley amb l’hidra d’aigua dolça no només van sorprendre els seus contemporanis per la seva espectacularitat, sinó que els seus resultats també van causar un enorme trasbals en la comunitat científica del seu temps. Idees com la «cadena del ser», el mecanisme de generació dels éssers vius o la mateixa naturalesa de l’ànima van ser fortament sacsejades.

Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

2016

Abstract Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective p…

Phosphorus limitation enhances parasite impact: feedback effects at the population level

2014

Background Nutrient deficiency affects the growth and population dynamics of consumers. Endoparasites can be seen as consumers that drain carbon (C) or energy from their host while simultaneously competing for limiting resources such as phosphorus (P). Depending on the relative demands of the host and the parasite for the limiting nutrient, intensified resource competition under nutrient limitation can either reduce the parasite’s effect on the host or further reduce the fitness of the nutrient-limited host. So far, knowledge of how nutrient limitation affects parasite performance at the host population level and how this affects the host populations is limited. Results We followed the popu…

Oxidative stress biomarkers in the copepod Limnocalanus macrurus from the northern Baltic Sea : effects of hydrographic factors and chemical contamin…

2015

The importance of phytoplankton production for carbon budgets in a semiarid floodplain wetland

2011

Phytoplankton production (PP) in wetlands is not measured as often as that of macrophytes. A three year-study during a period of sustained high flooding was undertaken in a central Spanish floodplain wetland (Las Tablas de Daimiel National Park) to determine net PP, its spatial heterogeneity and controlling factors, and compare it with primary production in macrophyte communities. This enabled us to estimate carbon budgets for each community. All PP variables showed high spatial and temporal variability among sites, resulting in low coherence even when flooding connected all sites. Net PP corresponded to 25- 36% of submerged plant production and 3-10% of helophyte production. Net PP was con…

Browning-induced changes in trophic functioning of planktonic food webs in temperate and boreal lakes: insights from fatty acids

2022

AbstractThe effects of lake browning on trophic functioning of planktonic food webs are not fully understood. We studied the effects of browning on the response patterns of polyunsaturated fatty acids and n−3/n−6 ratio in seston and compared them between boreal and temperate lakes. We also compared the regional differences and the effects of lake browning on the reliance of zooplankton on heterotrophic microbial pathways and the mass fractions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in zooplankton. Lake browning was associated with increasing phytoplankton biomass and concentrations of EPA and DHA in both temperate and boreal lakes, but the seston n−3/n−6 ratio was low…

An experimental model for mimicking biological systems: the Belousov-Zhabotinsky reaction in Lipid membranes

2006

La sépulture à char de La Tène A ancienne des “Craises” à Molinons (Yonne)

2013

The study reports on a chariot tomb excavated in 1985 at Les Craises in Molinons (Yonne). Set in an adventitious position in the midst of a monument with three quadrangular enclosures, the grave was of an adult of undetermined sex. Despite later pillaging, the goods found in this aristocratic tomb permit a dating to the second quarter of the 5th century BC, and an unusual cultural attribution, on the frontier in the Parisian Basin between the Jura culture to the south and the Marne-Moselle culture to the north.

Compte rendu de : Séverine Sofio, Artistes femmes. La parenthèse enchantée, XVIIIe-XIXe siècles, Paris, CNRS Éditions, 2016, 384 p.

2016

National audience; …

Contribution to thermal behaviour study of lithium-ion battery for electric and hybrid electric vehicle

2014

The main objectives of this study are to provide the essential information on the thermal behaviour of the battery cells for automotive purpose especially for EVs and HEVs through experimental work in order to develop an effective 3D electro-thermal model for lithium ion battery cells and pack. The experimental study is focusing on the distribution of temperature at various points of the battery cell surface, impact of different constant discharge rates, and also the importance of cooling system on the battery temperature behaviour. This thesis highlights the battery cell temperature under abuse discharge condition and the impact of stacking the battery cells inside the battery pack. Impact…